Struct rustacuda_core::DevicePointer

#[repr(transparent)]
pub struct DevicePointer<T: ?Sized>(_);

A pointer to device memory.

DevicePointer cannot be dereferenced by the CPU, as it is a pointer to a memory allocation in the device. It can be safely copied to the device (eg. as part of a kernel launch) and either unwrapped or transmuted to an appropriate pointer.

DevicePointer is guaranteed to have an equivalent internal representation to a raw pointer. Thus, it can be safely reinterpreted or transmuted to *mut T. It is safe to pass a DevicePointer through an FFI boundary to C code expecting a *mut T, so long as the code on the other side of that boundary does not attempt to dereference the pointer on the CPU. It is thus possible to pass a DevicePointer to a CUDA kernel written in C.

Methods

impl<T: ?Sized> DevicePointer<T>

pub unsafe fn wrap(ptr: *mut T) -> Self

Wrap the given raw pointer in a DevicePointer. The given pointer is assumed to be a valid, device pointer or null.

Safety

The given pointer must have been allocated with cuda_malloc or be null.

Examples

use rustacuda::memory::*;
use std::ptr;
unsafe {
    let null : *mut u64 = ptr::null_mut();
    assert!(DevicePointer::wrap(null).is_null());
}

pub fn as_raw(self) -> *const T

Returns the contained pointer as a raw pointer. The returned pointer is not valid on the CPU and must not be dereferenced.

Examples

use rustacuda::memory::*;
unsafe {
    let dev_ptr = cuda_malloc::<u64>(1).unwrap();
    let ptr: *const u64 = dev_ptr.as_raw();
    cuda_free(dev_ptr);
}

pub fn as_raw_mut(&mut self) -> *mut T

Returns the contained pointer as a mutable raw pointer. The returned pointer is not valid on the CPU and must not be dereferenced.

Examples

use rustacuda::memory::*;
unsafe {
    let mut dev_ptr = cuda_malloc::<u64>(1).unwrap();
    let ptr: *mut u64 = dev_ptr.as_raw_mut();
    cuda_free(dev_ptr);
}

pub fn is_null(self) -> bool

Returns true if the pointer is null.

Examples

use rustacuda::memory::*;
use std::ptr;
unsafe {
    let null : *mut u64 = ptr::null_mut();
    assert!(DevicePointer::wrap(null).is_null());
}

pub fn null() -> Self where
    T: Sized, 

Returns a null device pointer.

Examples:

use rustacuda::memory::*;
let ptr : DevicePointer<u64> = DevicePointer::null();
assert!(ptr.is_null());

pub unsafe fn offset(self, count: isize) -> Self where
    T: Sized, 

Calculates the offset from a device pointer.

count is in units of T; eg. a count of 3 represents a pointer offset of 3 * size_of::<T>() bytes.

Safety

If any of the following conditions are violated, the result is Undefined Behavior:

• Both the starting and resulting pointer must be either in bounds or one byte past the end of the same allocated object.

• The computed offset, in bytes, cannot overflow an isize.

• The offset being in bounds cannot rely on "wrapping around" the address space. That is, the infinite-precision sum, in bytes must fit in a usize.

Consider using wrapping_offset instead if these constraints are difficult to satisfy. The only advantage of this method is that it enables more aggressive compiler optimizations.

Examples

use rustacuda::memory::*;
unsafe {
    let mut dev_ptr = cuda_malloc::<u64>(5).unwrap();
    let offset = dev_ptr.offset(1); // Points to the 2nd u64 in the buffer
    cuda_free(dev_ptr); // Must free the buffer using the original pointer
}

pub fn wrapping_offset(self, count: isize) -> Self where
    T: Sized, 

Calculates the offset from a device pointer using wrapping arithmetic.

count is in units of T; eg. a count of 3 represents a pointer offset of 3 * size_of::<T>() bytes.

Safety

The resulting pointer does not need to be in bounds, but it is potentially hazardous to dereference (which requires unsafe). In particular, the resulting pointer may not be used to access a different allocated object than the one self points to. In other words, x.wrapping_offset(y.wrapping_offset_from(x)) is not the same as y, and dereferencing it is undefined behavior unless x and y point into the same allocated object.

Always use .offset(count) instead when possible, because offset allows the compiler to optimize better. If you need to cross object boundaries, cast the pointer to an integer and do the arithmetic there.

Examples

use rustacuda::memory::*;
unsafe {
    let mut dev_ptr = cuda_malloc::<u64>(5).unwrap();
    let offset = dev_ptr.wrapping_offset(1); // Points to the 2nd u64 in the buffer
    cuda_free(dev_ptr); // Must free the buffer using the original pointer
}

pub unsafe fn add(self, count: usize) -> Self where
    T: Sized, 

Calculates the offset from a pointer (convenience for .offset(count as isize)).

count is in units of T; e.g. a count of 3 represents a pointer offset of 3 * size_of::<T>() bytes.

Safety

If any of the following conditions are violated, the result is Undefined Behavior:

• Both the starting and resulting pointer must be either in bounds or one byte past the end of an allocated object.

• The computed offset, in bytes, cannot overflow an isize.

• The offset being in bounds cannot rely on "wrapping around" the address space. That is, the infinite-precision sum must fit in a usize.

Consider using wrapping_offset instead if these constraints are difficult to satisfy. The only advantage of this method is that it enables more aggressive compiler optimizations.

Examples

use rustacuda::memory::*;
unsafe {
    let mut dev_ptr = cuda_malloc::<u64>(5).unwrap();
    let offset = dev_ptr.add(1); // Points to the 2nd u64 in the buffer
    cuda_free(dev_ptr); // Must free the buffer using the original pointer
}

pub unsafe fn sub(self, count: usize) -> Self where
    T: Sized, 

Calculates the offset from a pointer (convenience for .offset((count as isize).wrapping_neg())).

count is in units of T; e.g. a count of 3 represents a pointer offset of 3 * size_of::<T>() bytes.

Safety

If any of the following conditions are violated, the result is Undefined Behavior:

• Both the starting and resulting pointer must be either in bounds or one byte past the end of an allocated object.

• The computed offset, in bytes, cannot overflow an isize.

• The offset being in bounds cannot rely on "wrapping around" the address space. That is, the infinite-precision sum must fit in a usize.

Consider using wrapping_offset instead if these constraints are difficult to satisfy. The only advantage of this method is that it enables more aggressive compiler optimizations.

Examples

use rustacuda::memory::*;
unsafe {
    let mut dev_ptr = cuda_malloc::<u64>(5).unwrap();
    let offset = dev_ptr.add(4).sub(3); // Points to the 2nd u64 in the buffer
    cuda_free(dev_ptr); // Must free the buffer using the original pointer
}

pub fn wrapping_add(self, count: usize) -> Self where
    T: Sized, 

Calculates the offset from a pointer using wrapping arithmetic. (convenience for .wrapping_offset(count as isize))

count is in units of T; e.g. a count of 3 represents a pointer offset of 3 * size_of::<T>() bytes.

Safety

The resulting pointer does not need to be in bounds, but it is potentially hazardous to dereference.

Always use .add(count) instead when possible, because add allows the compiler to optimize better.

Examples

use rustacuda::memory::*;
unsafe {
    let mut dev_ptr = cuda_malloc::<u64>(5).unwrap();
    let offset = dev_ptr.wrapping_add(1); // Points to the 2nd u64 in the buffer
    cuda_free(dev_ptr); // Must free the buffer using the original pointer
}

pub fn wrapping_sub(self, count: usize) -> Self where
    T: Sized, 

Calculates the offset from a pointer using wrapping arithmetic. (convenience for .wrapping_offset((count as isize).wrapping_sub()))

count is in units of T; e.g. a count of 3 represents a pointer offset of 3 * size_of::<T>() bytes.

Safety

The resulting pointer does not need to be in bounds, but it is potentially hazardous to dereference (which requires unsafe).

Always use .sub(count) instead when possible, because sub allows the compiler to optimize better.

Examples

use rustacuda::memory::*;
unsafe {
    let mut dev_ptr = cuda_malloc::<u64>(5).unwrap();
    let offset = dev_ptr.wrapping_add(4).wrapping_sub(3); // Points to the 2nd u64 in the buffer
    cuda_free(dev_ptr); // Must free the buffer using the original pointer
}

Trait Implementations

impl<T: ?Sized> Clone for DevicePointer<T>

fn clone(&self) -> Self

Returns a copy of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl<T: ?Sized> Copy for DevicePointer<T>

impl<T: ?Sized> Debug for DevicePointer<T>

fn fmt(&self, f: &mut Formatter) -> Result

Formats the value using the given formatter.

impl<T: ?Sized> DeviceCopy for DevicePointer<T>

impl<T: ?Sized> Eq for DevicePointer<T>

impl<T: ?Sized> Hash for DevicePointer<T>

fn hash<H: Hasher>(&self, h: &mut H)

Feeds this value into the given [Hasher].

fn hash_slice<H>(data: &[Self], state: &mut H) where
    H: Hasher, 

Feeds a slice of this type into the given [Hasher].

impl<T: ?Sized> Ord for DevicePointer<T>

fn cmp(&self, other: &DevicePointer<T>) -> Ordering

This method returns an [Ordering] between self and other.

#[must_use] fn max(self, other: Self) -> Self

Compares and returns the maximum of two values.

#[must_use] fn min(self, other: Self) -> Self

Compares and returns the minimum of two values.

#[must_use] fn clamp(self, min: Self, max: Self) -> Self

🔬 This is a nightly-only experimental API. (clamp)

Restrict a value to a certain interval.

impl<T: ?Sized> PartialEq<DevicePointer<T>> for DevicePointer<T>

fn eq(&self, other: &DevicePointer<T>) -> bool

This method tests for self and other values to be equal, and is used by ==.

#[must_use] fn ne(&self, other: &Rhs) -> bool

This method tests for !=.

impl<T: ?Sized> PartialOrd<DevicePointer<T>> for DevicePointer<T>

fn partial_cmp(&self, other: &DevicePointer<T>) -> Option<Ordering>

This method returns an ordering between self and other values if one exists.

#[must_use] fn lt(&self, other: &Rhs) -> bool

This method tests less than (for self and other) and is used by the < operator.

#[must_use] fn le(&self, other: &Rhs) -> bool

This method tests less than or equal to (for self and other) and is used by the <= operator.

#[must_use] fn gt(&self, other: &Rhs) -> bool

This method tests greater than (for self and other) and is used by the > operator.

#[must_use] fn ge(&self, other: &Rhs) -> bool

This method tests greater than or equal to (for self and other) and is used by the >= operator.

impl<T: ?Sized> Pointer for DevicePointer<T>

fn fmt(&self, f: &mut Formatter) -> Result

Formats the value using the given formatter.